Machine for forming thermoplastic bag-tubing



Sept. 10, 1957 A. P. KLASING ET AL 2,8

MACHINE FOR FORMING THERMOPLASTIC BAG-TUBING Original Filed May 14; 1954 2 Sheets-Sheet l INVENTORS ARTHUR H KLASING WILLIAM J. RICE Sept. 10, 1957 A. P. KLASING ETAL 2,

MACHINE FOR FORMING THERMOPLASTIC BAG-TUBING Original Filed May 14, 1954 2 Sheets$heet 2 INVENTOR. ARTHUR P. KLASING WILLIAM J. RICE ATTORNY United States Patent ,MAGHINE FGR FURMING THERMOPLASTIC BAG-TUBING Arthur l .v Klasing, Webster Groves, and William J. Rice, ,University City, Moi, assignors to Central States Paper & Bag Co., St. Louis, Mo, a corporation of Missouri Original application May 14, 1954, Serial No. 429,853. Divided and this application January 12,1956, Serial No.,558,,696

'8 Claims. (Cl. 154-42) This invention relates in general to tubing, ,bags, and similar fabricated materials for enclosing articles capable of being packaged and, more particularly, to certain new and useful improvements in such packaging materials and inmeans and methods of making the same. This application is a division of our co-pending application .SerialNo. 429,853, filed May 14, 1 954.

Itis the primary object of the present invention to provide .,means for fabricating thermoplastic synthetic resin films, such as polyethylene and the like, into packa ing materials, such as bag-forming tubing and bags made from such tubing.

It is another object of the present invention to provide means and methods for manufacturing packaging materials of the type stated from thermoplastic synthetic resin films in a highly economical, continuous, eflicient and rapid manner.

,It is a further object of the present invention to provide a packaging device in the nature of a bag which is :uniquely adapted for enclosing meat, poultry, or any other-articles of merchandise suitable for display and sale inretail shops, department stores, supermarkets, and the like.

'With'the above and other objects in view, our invention resides in the novel features of form, construction, arrangement, and combination of parts presently described-and pointed out in the claims.

In the accompanying drawings (two sheets)- Figure 1 is a schematic view of a machinery embodying the present invention and being adapted for making bag-forming tubing from themoplastic synthetic resin films:

;Figure 2 is a fragmentary sectional view takenmalong line,2;2 of Figure 1;

Figure 3 is a schematic view of machinery embodying the present'invention and being adapted for making bags outof the bag-forming tubing;

Figure 4 is a plan view of a bag constructedtin accordance with and embodying the present invention;

Figure 5 is a transverse sectional view taken along line 5-5 of Figure 4; and

Figure 6 isa fragmentary sectional view taken along line 6-6 of Figure 4.

Referring now in more detail and by reference characters to the drawings, which illustrate a preferred embodiment of the. present invention, A designates a tube- ;forming machine which comprises two supply-shafts 1, 2,

for-respectively supporting rolls 3,4, of thermoplastic synthetic resin films, such as polyethylene orthe l1ke,

,zmd from .which two separate continuous webs w,,.w, of :film may be withdrawn, the webs w, w, preferably, though not necessarily, being of equal .width and arranged in marginal registration. Operatively mounted yimspaced parallel relation to the supply-shafts 1, 2, are tensioning rolls 5, 6, around which the webs w, w, are respectively trained and brought into facewise marginally registered abutment for passage between the first pair of co-operating feed rolls 7, 8, which are also disposed in parallel relation .to the shafts, 1,2. Similarly mounted in spaced paraHel relation to the-feed rolls 7, 8, and forwardly therefrom ,along the path of travel of the combined webs w, w, is a large diameter platen-roll 9 and a second pair of, feed rol1s10, 11. Operatively mounted beyond the second pair offeed rolls 10, 11,Vare,separate rewindshafts 12, 13. The bearings for the shafts 1, 2, 12,13, the adjustable trunnions for thetcnsioningrolls 5, 6,. .th e gear-drive for the-feed rolls 7, 8, 10, 11, and the platenroll 9 have notbeen shown inasmuchias such elements are conventional and well understood in connection with winding and reelingimachinery. .It is merely sufficient for present purposes tonotethatpthe driving and Webtensioning mechanism should .co-act and :co-operate to keep both webs w,tw,. taut withoutbreaking and moving together at identical, lineal speed so as topass around the platen, roll 9 in snug unwrinkled contact against the surface thereof.

-Rigidly' mounted in outwardly spa ced parallel relation to the platen-roll9is adovet'ail bar 14 for supportingfia plurality ofelectrically or..electronic heated sealerslS,

each including a base-block 16 having a dovetail slot- 17 bar 14 to any desired positionof adjustmentvto accommodate the width of vthe webs -w, w', and then tightly secured in such uadjustedposition. Secured to the baseblock .16 by means of adjusting screws 19, 19',:is a

sealer-bar 20.provided.,at its outer end with a-wedgeshaped sealer-head21 internally. equipedwitha conventional resistance-typeelectnic heating element 22 and having a narrow somewhat rounded sealing .edge 23.

The sealer-bars 20 may be adjusted inwardly or outwardly with respect to the base-blocks 16 by appropriate setting of the screws-19,19, so thattheouter sealers 15 will; press the registeringedges. of thetwebs w, w', down with sufficient pressure and temperature to fuse them together. The central sealer 15:is,adju.sted so as to be practically in contact with the surface of. the platen-roll 9-andtslit and sealthe webs w, w, at the same time,,,a s shown in Figure 2, thereby, forming two continuous webs Ofedge-sealed flat, tubing 2, which are separately rolled up ,on the rewind shafts I12, 13, respectively. It will, of course, be understood that by using more than one. intermediatesealer 15, it is, possible to form more tharrtwo webs of tubing.

,Bagscan .be formed from the rolls of tubing tby placing, one of such rolls upon an unwind shaft 24 and feeding the tubing t preferably in a horizontal direction betweenintermittently drivenfeed rolls 25, 26, andz beneath a verticallyreciprocating cutting-blade or knife ,27 adapted to .cut the, tubing i :intosections of desired length. Operatively mounted along the path of travel of the tubing teforwardlyt with respectto theknife'27 is a flat platen 28 andfla vertically.reciprocating electrically heated diet-plates adapted to sever and. seal the sections ,alongantarcuate line;in,the provision .of a bottom seams ,andetherebyt forming thesectioninto a completed bag B.

Interposed between the flat platen ,28 :and the knife 27 is anaccelerating transfer-belt 30 forshifting each outscotion forwardly onto the .platen 28beneath theidie-plate29. The drivingmechanismifor. the rolls, 2f5,.,26,' the,knife 27,

.the die-plate 29. and the transfer-belt 3.0 is entirely corn belt 30 beneath the die-plate 29 and during the dwell in thisfeeding movement the die-plate 29 is shifted down Wardly to complete the bag B. The crescent-shaped strip of excess material e, of'course, may be discarded as scrap. By suitable variation in the shape of the rule on the dieplate, and the position thereof in relation to the opposite ends of the cut-off sections, it is possible to form two bags at once. a

The completed bag B thus comprises two overlying identically shaped panels 31, 32, secured together along their longitudinal margins and across the bottom by a continuous and uninterrupted heat-sealed seam 33, which consists in part of the seam s formed by the die-plate Z9 and in part by the marginal seals formed by the sealers 15.

By employing a transparent film for the web w and an opaque preferably white film for the web w, the bottom or back panel 32 of the bag B, when completed, will be opaque and atford an excellent display package for meats, poultry, and the like, since such food products can be placed in such a bag with the more attractive sides presented toward the transparent panel 31 and the visceral or less attractive sides toward the opaque panel 32. The bag B, when completed, has a wide mouthed or open top, so that such food products can be readily disposed therein. When suitably filled, the bag B can be heat-sealed, stapled shut, or otherwise conventionally closed.

It should be understood that changes and modifications in the form, construction, arrangement, and combination of the several parts of the packaging materials and means and methods of making the same may be made and substituted for those herein shown and described without departing from the nature and principle of our invention.

Having thus described our invention, what we claim and desire to secure by Letters Patent is:

1. A machine for forming thermoplastic bag-tubing, said machine comprising a pair of spaced parallel rollsupports for operatively holding two rolls of thin thermoplastic sheeting, means for drawing the thermoplastic sheeting from the roll in two marginally aligned webs, a pair of feed rolls for bringing the webs together in facewise overlying relation, and relatively. narrow heated elements for simultaneously sealing the webs together along a plurality of spaced parallel thin seal-lines and severing the webs within the area of such lines to form a plurality of spaced parallel lengths of edge-sealed tubing.

2. A machine for forming thermoplastic bag-tubing, said machine comprising a pair of spaced parallel rollsupports for operatively holding two rolls of thin thermor plastic sheeting, power-driven means for drawing the thermoplastic sheeting from the roll in two marginally aligned webs, a pair of feed rolls for bringing the webs together in facewise overlying relation, and relatively narrow heated elements for simultaneously sealing the webs together along a plurality of spaced parallel thin seal-lines and severing the webs within the area of such lines to form a plurality of spaced parallel lengths of edge-sealed tubing.

3. A machine for forming thermoplastic bag-tubing, said machine comprising a pair of spaced parallel roll supports for operatively holding two rolls of thin thermo" plastic sheeting, means for drawing the thermoplastic sheeting from the roll in two marginally aligned webs, a pair of feed rolls for bringing the webs together in face wise overlying relation and means for simultaneously sealing the webs together along a plurality of spaced parallel thin seal-lines and severing the webs within the area of such lines to form a plurality of spaced parallel lengths of edge-sealed tubing.

4. A machine for forming thermoplastic bag-tubing,

said machine comprising a pair of spaced parallel rollsupports for operatively holding two rolls of thin thermoplastic sheeting, means for drawing the thermoplastic sheeting from the roll in two marginally aligned webs, a pair of feed rolls for bringing the webs together in facewise overlying relation, and transversely adjustable means for simultaneously sealing the webs together along a plurality of spaced parallel thin seal-lines and severing the webs within the area of such lines to form a plurality of spaced parallel lengths of edge-sealed tubing.

5. A machine for forming thermoplastic bag-tubing, said machine comprising a pair of spaced parallel rollsupports for operatively holding two rolls of thin thermoplastic sheeting, means for drawing the thermoplastic sheeting from the roll in two marginally aligned webs, a pair of: feed rolls for bringing the webs together in facewise overlying relation, and electrically heated means for simultaneously sealing the webs together along a plurality of spaced parallel thin seal-lines and severing the webs within the area of such lines to form a plurality of spaced parallel lengths of edge-sealed tubing. 7 p

6. A machine for forming thermoplastic bag-tubing, said machine comprising a pair of spaced parallel rollsupports for operatively holding two rolls of thin thermoplastic sheeting, means for drawing the thermoplastic sheeting from the roll in two marginally aligned webs, a

pair of feed rolls for bringing the webs together in facewise overlying relation, and electrically heated transversely adjustable means for simultaneously sealing the webs together along a plurality of spaced parallel thin seal-lines and severing the webs within the area of such lines to form a plurality of spaced parallel lengths of edgesealed tubing.

7. A machine for forming thermoplastic bag-tubing, said machine comprising a pair of spaced parallel rollsupports for operatively holding two rolls of thin thermoplastic sheeting, means for drawing the thermoplastic sheeting from the roll. in two marginally aligned webs, a pair of feed rolls for bringing the webs together in facewise overlying relation, a platen roll disposed in the path of said web so that the web will pass over and around said platen roll, and means for simultaneously sealing the webs together along a plurality of spaced parallel thin seal-lines and severing the webs within the area of such lines to form a plurality of spaced parallel lengths of edge-sealed tubing.

8. A machine for forming thermoplastic bag-tubing, said machine comprising a pair of spaced parallel rollsupports for operatively holding two rolls of thin thermoplastic sheeting, means for drawing the thermoplastic sheeting from the roll in two marginally aligned webs, a pair of feed rolls for bringing the webs together in facewise overlying relation, a platen roll disposed in the path of said web so that the web will pass over and around said platen roll, and means for simultaneously sealing the webs together along a plurality of spaced parallel thin seal-lines and severing the webs within the area of such lines to 'form a plurality of spaced parallel lengths of edgesealed tubing, said last-named means being located over the platen roll and being adapted to press the webs against the platen roll as the seal-lines and slits are formed.

References Cited inthe file of this patent UNITED STATES PATENTS 

